At the start of a 50K trail race, almost anything sounds edible.

Your legs are fresh. Your stomach feels calm. You packed enough gels for an expedition. You’re convinced your fueling plan is dialled.

Then hour four arrives.

The sweetness starts becoming harder to tolerate. Your mouth feels dry. Your stomach suddenly feels fragile. You still need energy, but the thought of another sticky gel feels almost offensive.

This is one of the biggest differences between shorter races and long trail running:

Fueling becomes psychological as much as physical.

And if there’s one thing experienced ultra runners learn quickly, it’s this:

The problem usually isn’t just energy.

It’s the ability to keep eating.

We explored this idea further in our article on why energy gels start making runners feel sick during long runs

Why Fueling a 50K Is Different From a Marathon

A 50K trail race might only sound slightly longer than a marathon on paper, but nutritionally, they can feel completely different.

Trail races usually involve:

• more time on feet
• elevation gain
• technical terrain
• changing temperatures
• altitude
• slower pacing
• longer digestion stress

A road marathon might take 3–5 hours.

A mountainous 50K can easily become 6, 7, 8 hours or more.

That changes everything.

Because the longer the effort lasts, the more your fueling strategy shifts away from pure carbohydrate delivery and toward something much more human:

• appetite
• comfort
• digestion
• texture
• flavour fatigue
• emotional tolerance

This is why many trail runners who tolerate gels perfectly during shorter sessions suddenly struggle during ultras.

Not because they’re weak.

Because endurance changes the relationship between food and performance.

What to Eat Before a 50K Trail Race

The goal before a long trail race isn’t to eat perfectly.

It’s to arrive at the start line feeling healthy, calm, and fuelled up.

If stomach issues are already part of your long runs, our guide on why digestion might be the missing piece in your athletic performance goes deeper into how endurance exercise affects the gut.

For most runners, that means sticking to familiar foods that are:

• carbohydrate-rich
• easy to digest
• low in digestive stress

Good examples include:

• oats
• toast with honey or nut butter
• rice
• bananas
• yoghurt
• eggs
• simple sandwiches

Hydration matters too - especially during hot races or alpine events.

Homemade hydration strategies can also help during long mountain races - especially in hotter conditions. Here’s our guide to making your own natural isotonic drink.

One of the biggest mistakes runners make before long races is trying something unfamiliar.

Race morning is not the time to experiment with miracle superfoods or aggressive fueling hacks.

Simple and familiar usually wins.

What to Eat During the First 2 Hours

The first hours of a trail race are often deceptively easy.

Your appetite still works.

Energy feels stable (as you're using your glycogen reserves)

And most foods still sound appealing.

This is actually the best time to fuel consistently.

Many experienced runners start eating early rather than waiting until hunger appears.

Small amounts every 10–30 minutes

The key is rhythm, not panic.

Because once fueling falls behind during a long race, catching up becomes much harder.

What Happens After 4+ Hours of Running

This is where trail nutrition becomes interesting.

And difficult.

After several hours, many runners experience:

• sweetness fatigue
• nausea
• dry mouth
• stomach discomfort
• bloating
• complete loss of appetite
• even cramping

Even when they still desperately need energy.

This is one of the reasons long-distance fueling becomes such a mental challenge.

Because eventually, eating stops feeling automatic.

You begin forcing things down.

And ironically, the sweeter your nutrition becomes, the harder it can feel to continue.

This is the moment many endurance athletes recognise instantly:

“I genuinely cannot eat another gel.”

It’s also why so many runners begin searching for different textures and flavours later in races.

You can read more about this in our guide:
Why Do Energy Gels Make Me Feel Sick During Long Runs?

Why Many Ultra Runners Start Craving Savoury Foods

Walk through an ultra-marathon aid station after several hours, and you’ll notice something fascinating.

People stop obsessing over sweetness.

Suddenly, everyone wants:

• soup
• potatoes
• bread
• noodles
• salty snacks
• rice
• broth

Not because carbohydrates stopped mattering.

But because savoury foods can become psychologically easier to tolerate during long efforts.

This is one of the most misunderstood parts of endurance nutrition.

Fueling long races isn’t only about physiology.

It’s also about maintaining the desire to keep eating.

And flavour variety plays a huge role in that.

This is especially true during:

• mountain ultras
• gravel races
• ski touring
• long cycling adventures
• hot races
• technical trail events

Because eventually, your brain gets tired too.

We talk more about this balance between sweet and savoury fueling in:

• The Beauty of Balance: Why Yanaa’s Savoury Pouches Are Changing Sports Nutrition

• Not All Sports Nutrition Is Equal

Mixing Sweet and Savoury Fuel During a 50K

Most experienced ultra runners don’t rely on just one type of fuel.

Instead, they rotate.

A typical strategy might include:

• gels during climbs or hard efforts
• isotonic drinks between aid stations
• bananas or bars early in the race
• savoury foods later when sweetness becomes difficult

This is exactly where products like Yanaa fit naturally into endurance fueling.

Not as a replacement for everything else.

But as a savoury layer within a broader fueling strategy — something that helps maintain appetite, variety, and consistency during long mountain days. 

Because when fueling becomes impossible to tolerate, performance usually falls apart soon after.

Example 50K Trail Race Fueling Strategy

Every athlete is different, but a balanced 50K fueling strategy could look something like this:

Before the race

• oats with banana
• coffee
• toast
• hydration

Hours 1-2

• gels
• isotonic drink
• small consistent intake

Hours 3-5

• bananas
• rice cakes
• broth
• savoury foods
• softer textures
• hydration focus

Final hours

• smaller regular calories
• easy digestion
• sodium
• whatever still feels edible

The best fueling strategy is rarely the most “perfect.”

It’s the one you can realistically continue using for hours.

Common 50K Fueling Mistakes

Waiting too long to eat

If you only start fueling once you feel empty, you’re already behind.

Relying only on sweet products

Many runners eventually hit flavour fatigue during long races.

Ignoring hydration

Dehydration often makes stomach problems much worse.

Trying new products on race day

Your stomach loves familiarity.

Eating huge amounts at once

Smaller, more regular intake is often easier to tolerate.

Fighting your stomach

Sometimes slowing down briefly helps digestion recover.

Real Food vs Energy Gels for Trail Running

This doesn’t need to be a war.

Energy gels can work extremely well:

• fast carbohydrates
• practical
• lightweight
• easy to carry

Real foods also offer advantages:

• texture variety
• savoury flavours
• psychological comfort
• gentler eating experience for some athletes

The smartest trail runners usually combine both.

Because trail nutrition isn’t about ideology.

It’s about continuing to fuel when conditions become difficult.

Final Thoughts

The best 50K fueling strategy isn’t necessarily the most scientific one.

It’s the one that still works six hours later.

The one that helps you keep eating when your appetite disappears.

The one that feels sustainable not just physically, but mentally too.

Because during long mountain races, the wall often isn’t your legs.

It’s your stomach.

And sometimes the solution isn’t more sweetness.

It’s balance.

Frequently Asked Questions

How many calories should you eat during a 50K?

This varies between athletes, pace, and conditions, but most runners aim for consistent calorie intake throughout the race rather than large infrequent meals.

What foods are easiest to digest during trail races?

Popular options include bananas, rice cakes, potatoes, isotonic drinks, soft bars, broth, and softer savoury foods.

Are energy gels enough for a 50K?

For some runners yes, but many athletes eventually introduce more variety during longer races to reduce sweetness fatigue and stomach issues.

Why do ultra runners eat potatoes?

Potatoes provide easy-to-digest carbohydrates, salt, and a savoury flavour that many runners crave later in races.

Can savoury foods help during ultras?

For many athletes, yes. Savoury foods can reduce flavour fatigue and help maintain appetite during long efforts.

What causes nausea during long trail races?

Common causes include dehydration, digestive stress, heat, intensity, underfueling, overfueling, and repeated exposure to very sweet nutrition.